Wireless communication method, base station, transmission/reception point, user equipment and wireless communication system

ABSTRACT

The present disclosure provides a wireless communication method, a transmission/reception point, a user equipment and a wireless communication system, the wireless communication method comprising a step of: receiving the UL/DL configuration for the UE in a common search space of a specific time/frequency resource associated with a specific TP/RP, wherein, the UE is attached to the specific TP/RP, and the association between a number index of the specific TP/RP and an index of the specific time/frequency resource is predefined.

TECHNICAL FIELD

The present disclosure relates to the communication field, and inparticular, to a wireless communication method, a base station, atransmission/reception point, a user equipment and a wirelesscommunication system.

BACKGROUND ART

eIMTA (Further Enhancements to Long Term Evolution (LTE) Time DivisionDuplexing (TDD) for Downlink-Uplink (DL-UL) Interference Management andTraffic Adaptation) is one work item (WI) topic in 3GPP LTE Rel.12 andtargeted to adapt traffic by modifying TDD UL/DL configuration. One ofthe main focuses is to enable fast TDD UL/DL configuration to realizetraffic adaptation. Currently the TDD UL/DL configuration information iscarried in System Information Block 1 (SIB1) and the variation period is640 ms. One of the discussion points is how to transmit TDD UL/DLconfiguration information in physical layer (L1).

So far, there are generally four options about the fast TDD UL/DLconfiguration signaling transmission: (1) implicit signaling; (2)explicit L1 signaling of reconfiguration by common search space (CSS);(3) explicit L1 signaling by user equipment specific Physical DownlinkControl Channel (UE-specific PDCCH); and (4) explicit MAC signaling.Among them, Option 2) is most promising from signaling overhead, and issupported almost by most companies.

One problem of option (2) is how different transmission point/receptionpoints (TP/RPs) distinguish their own TDD UL/DL configurationtransmitted in CSS in Coordinated Multi-point (CoMP) scenario,especially CoMP scenario 4.

In particular, FIG. 1 is a diagram schematically showing “CoMP scenario4” 100 in LTE, wherein a macro point (also referred to as the macro basestation, the base station hereinafter) 101 and three TP/RPs comprisingthe pico points 102, 103 and 104 share the same common signal/channels.That is, UEs in the macro point 101 (e.g., UE 106) and UEs in the picopoints 102-104 (e.g., UE 105 in the pico point 104) share the same UL/DLconfiguration transmitted in the same CSS. For different TP/RPs, forexample, TP/RPs 102, 103 and 104, they cannot have different TDD UL/DLconfiguration to adapt to their own uplink/downlink traffic,respectively. All TP/RPs have to share the same TDD UL/DL configuration.

SUMMARY OF THE DISCLOSURE

The present disclosure is made in consideration of the above aspects.

According to a first aspect of the present disclosure, a wirelesscommunication method of receiving uplink/downlink (UL/DL) configurationby a user equipment (UE), in a wireless communication system includingmultiple transmission/reception points (TP/RPs), comprising a step of:receiving the UL/DL configuration for the UE in a common search space ofa specific time/frequency resource associated with a specific TP/RP,wherein, the UE is attached to the specific TP/RP, and the associationbetween a number index of the specific TP/RP and an index of thespecific time/frequency resource is predefined.

According to a second aspect of the present disclosure, a wirelesscommunication method of transmitting uplink/downlink (UL/DL)configuration by a base station, in a wireless communication systemincluding multiple transmission/reception points (TP/RPs), comprising astep of: transmitting UL/DL configuration to a user equipment (UE)attached to a specific TP/RP, in a common search space of a specifictime/frequency resource associated with the specific TP/RP; wherein, theassociation between a number index of the specific TP/RP and an index ofthe specific time/frequency resource is predefined.

According to a third aspect of the present disclosure, a wirelesscommunication method of receiving uplink/downlink (UL/DL) configurationby a user equipment (UE), in a wireless communication system includingmultiple transmission/reception points (TP/RPs), comprising a step of:receiving the UL/DL configuration for the UE from a specific TP/RP, in aUE specific search space of a specific time/frequency resourceassociated with the specific TP/RP, wherein, the UE is attached to thespecific TP/RP, and the association between a number index of thespecific TP/RP and an index of the specific time/frequency resource ispredefined.

According to a fourth aspect of the present disclosure, a wirelesscommunication method of transmitting uplink/downlink (UL/DL)configuration by a transmission/reception point (TP/RP), in a wirelesscommunication system including multiple TP/RPs, comprising a step of:transmitting UL/DL configuration to a user equipment (UE) attached tothe TP/RP, in a UE specific search space of a specific time/frequencyresource associated with the TP/RP; wherein, the association between anumber index of the TP/RP and an index of the specific time/frequencyresource is predefined.

According to a fifth aspect of the present disclosure, a wirelesscommunication method of receiving uplink/downlink (UL/DL) configurationby a user equipment (UE), in a wireless communication system includingmultiple transmission/reception points (TP/RPs), comprising a step of:receiving the UL/DL configuration for the UE in a UE group common searchspace of a common search space of a specific time/frequency resourceassociated with a specific UE group, wherein, the UE is grouped into thespecific UE group, and the association between a number index of thespecific UE group and an index of the specific time/frequency resourceis predefined.

According to a sixth aspect of the present disclosure, a wirelesscommunication method of transmitting uplink/downlink (UL/DL)configuration by a base station, in a wireless communication systemincluding multiple transmission/reception points (TP/RPs), comprising astep of: transmitting the UL/DL configuration to a user equipment (UE),in a UE group common search space of a common search space of a specifictime/frequency resource associated with a specific UE group; wherein,the UE is grouped into the specific UE group, and the associationbetween a number index of the specific UE group and an index of thespecific time/frequency resource is predefined.

According to a seventh aspect of the present disclosure, a wirelesscommunication method of receiving uplink/downlink (UL/DL) configurationby a user equipment (UE), in a wireless communication system includingmultiple transmission/reception points (TP/RPs), comprising a step of:receiving the UL/DL configuration for the UE from a TP/RP to which it isattached, in a UE group common search space of a UE specific searchspace of a specific time/frequency resource associated with a specificUE group, wherein, the UE is grouped into the specific UE group, and theassociation between a number index of the specific UE group and an indexof the specific time/frequency resource is predefined.

According to an eighth aspect of the present disclosure, a wirelesscommunication method of transmitting uplink/downlink (UL/DL)configuration by a transmission/reception point (TP/RP), in a wirelesscommunication system including multiple TP/RPs, comprising a step of:transmitting the UL/DL configuration to a user equipment (UE) attachedto the TP/RP, in a UE group common search space of a UE specific searchspace of a specific time/frequency resource associated with a specificUE group; wherein, the UE is grouped into the specific UE group, and theassociation between a number index of the specific UE group and an indexof the specific time/frequency resource is predefined.

According to a ninth aspect of the present disclosure, a user equipment(UE) of receiving uplink/downlink (UL/DL) configuration in a wirelesscommunication system including multiple transmission/reception points(TP/RPs), comprising: a receiver which receives the UL/DL configurationfor the UE in a common search space of a specific time/frequencyresource associated with a specific TP/RP, wherein, the UE is attachedto the specific TP/RP, and the association between a number index of thespecific TP/RP and an index of the specific time/frequency resource ispredefined.

According to a tenth aspect of the present disclosure, a base station oftransmitting uplink/downlink (UL/DL) configuration, in a wirelesscommunication system including multiple TP/RPs, comprising: atransmitter which transmits the UL/DL configuration to a user equipment(UE), in a common search space of a specific time/frequency resourceassociated with a specific TP/RP; wherein, the UE is attached to thespecific TP/RP, and the association between a number index of thespecific TP/RP and an index of the specific time/frequency resource ispredefined.

According to an eleventh aspect of the present disclosure, a userequipment (UE) of receiving uplink/downlink (UL/DL) configuration in awireless communication system including multiple transmission/receptionpoints (TP/RPs), comprising: a receiver which receives the UL/DLconfiguration for the UE from a specific TP/RP, in a UE specific searchspace of a specific time/frequency resource associated with the specificTP/RP, wherein, the UE is attached to the specific TP/RP, and theassociation between a number index of the specific TP/RP and an index ofthe specific time/frequency resource is predefined.

According to a twelfth aspect of the present disclosure, atransmission/reception point (TP/RP) of transmitting uplink/downlink(UL/DL) configuration, in a wireless communication system includingmultiple TP/RPs, comprising: a transmitter which transmits UL/DLconfiguration to a user equipment (UE) attached to the TP/RP, in a UEspecific search space of a specific time/frequency resource associatedwith the TP/RP; wherein, the association between a number index of theTP/RP and an index of the specific time/frequency resource ispredefined.

According to a thirteenth aspect of the present disclosure, a userequipment (UE) of receiving uplink/downlink (UL/DL) configuration, in awireless communication system including multiple transmission/receptionpoints (TP/RPs), comprising: a receiver which receives the UL/DLconfiguration for the UE in a UE group common search space of a commonsearch space of a specific time/frequency resource associated with aspecific UE group, wherein, the UE is grouped into the specific UEgroup, and the association between a number index of the specific UEgroup and an index of the specific time/frequency resource ispredefined.

According to a fourteenth aspect of the present disclosure, a basestation of transmitting uplink/downlink (UL/DL) configuration, in awireless communication system including multiple transmission/receptionpoints (TP/RPs), comprising: a transmitter which transmits the UL/DLconfiguration to a user equipment (UE), in a UE group common searchspace of a common search space of a specific time/frequency resourceassociated with a specific UE group; wherein, the UE is grouped into thespecific UE group, and the association between a number index of thespecific UE group and an index of the specific time/frequency resourceis predefined.

According to a fifteenth aspect of the present disclosure, a userequipment (UE) of receiving uplink/downlink (UL/DL) configuration, in awireless communication system including multiple transmission/receptionpoints (TP/RPs), comprising: a receiver which receives the UL/DLconfiguration for the UE from a TP/RP to which it is attached, in a UEgroup common search space of a UE specific search space of a specifictime/frequency resource associated with a specific UE group, wherein,the UE is grouped into the specific UE group, and the associationbetween a number index of the specific UE group and an index of thespecific time/frequency resource is predefined.

According to an sixteenth aspect of the present disclosure, atransmission/reception point (TP/RP) of transmitting uplink/downlink(UL/DL) configuration, in a wireless communication system includingmultiple TP/RPs, comprising: a transmitter which transmits the UL/DLconfiguration to a user equipment (UE) attached to the TP/RP, in a UEgroup common search space of a UE specific search space of a specifictime/frequency resource associated with a specific UE group; wherein,the UE is grouped into the specific UE group, and the associationbetween a number index of the specific UE group and an index of thespecific time/frequency resource is predefined.

According to a seventeenth aspect of the present disclosure, a wirelesscommunication system, comprising: a first transmission/reception point(TP/RP), which transmits a first uplink/downlink (UL/DL) configurationto user equipments (UEs) in its coverage in a common search space of afirst time/frequency resource associated with the first TP/RP; a secondTP/RP, which transmits a second UL/DL configuration to UEs in itscoverage in a common search space of a second time/frequency resourceassociated with the second TP/RP; a base station which transmits thefirst uplink/downlink UL/DL configuration to UEs in its coverage in thecommon search space of the first time/frequency resource, and transmitsthe second UL/DL configuration to UEs in its coverage in the commonsearch space of the second time/frequency resource; a first UE attachedto the first TP/RP, which receives the first UL/DL configuration in thecommon search space of the first time/frequency resource; and a secondUE attached to the second TP/RP, which receives the second UL/DLconfiguration in the common search space of the second time/frequencyresource; wherein, the association between a number index of TP/RP andan index of time/frequency resource is predefined at the base station,the first TP/RP, the second TP/RP, the first UE and the second UE.

According to an eighteenth aspect of the present disclosure, a wirelesscommunication system, comprising: a base station; a firsttransmission/reception point (TP/RP) which transmits a firstuplink/downlink (UL/DL) configuration to user equipments (UEs) in itscoverage, in a UE specific common search space of a first time/frequencyresource; a second TP/RP which transmits a second UL/DL configuration toUEs in its coverage, in a UE specific common search space of a secondtime/frequency resource; a first UE attached to the first TP/RP, whichreceives the first UL/DL configuration from the first TP/RP, in the UEspecific common search space of the first time/frequency resource; and asecond UE attached to the second TP/RP, which receives the second UL/DLconfiguration from the second TP/RP, in the UE specific common searchspace of the second time/frequency resource; wherein, the associationbetween a number index of TP/RP and an index of time/frequency resourceis predefined at the first TP/RP, the second TP/RP, the first UE and thesecond UE.

According to a nineteenth aspect of the present disclosure, a wirelesscommunication system, comprising: a first transmission/reception point(TP/RP), which transmits a first UL/DL configuration to user equipments(UEs) in its coverage, in a UE group common search space of a commonsearch space of a first time/frequency resource associated with a firstUE group; a second TP/RP, which transmits a second UL/DL configurationto UEs in its coverage, in a UE group common search space of a commonsearch space of a second time/frequency resource associated with asecond UE group; a base station which transmits the first UL/DLconfiguration to UEs in its coverage in the UE group common search spaceof the common search space of the first time/frequency resource, andtransmits a second UL/DL configuration to UEs in its coverage in the UEcommon group search space of the common search space of the secondtime/frequency resource; a first UE in the first UE group, whichreceives the first UL/DL configuration, in the UE group common searchspace of the common search space of the first time/frequency resource;and a second UE in the second UE group, which receives the second UL/DLconfiguration, in the UE group common search space of the common searchspace of the second time/frequency resource; wherein, the associationbetween a number index of UE group and an index of time/frequencyresource is predefined at the base station, the first TP/RP, the secondTP/RP, the first UE and the second UE.

According to a twentieth aspect of the present disclosure, a wirelesscommunication system, comprising: a base station; a firsttransmission/reception point (TP/RP), which transmits a first UL/DLconfiguration to user equipments (UEs) in its coverage, in a UE groupcommon search space of a UE specific search space of a firsttime/frequency resource associated with a first UE group; a second TP/RPwhich transmits a second UL/DL configuration to UEs in its coverage, ina UE group common search space of a UE specific search space of a secondtime/frequency resource associated with a second UE group; a first UE inthe first UE group, which receives the first UL/DL configuration fromthe first TP/RP, in the UE group common search space of the UE specificsearch space of the first time/frequency resource; and a second UE inthe second UE group, which receives the second UL/DL configuration fromthe second TP/RP, in the UE group common search space of the UE specificsearch space of the second time/frequency resource; wherein, theassociation between a number index of UE group and an index oftime/frequency resource is predefined at the first TP/RP, the secondTP/RP, the first UE and the second UE.

According to the wireless communication method, the base station, thetransmission/reception point, the user equipment and the wirelesscommunication system of some aspects of the present disclosure,different TP/RPs may have their own TDD UL/DL configuration to adapt totheir own uplink/downlink traffic even when the different TP/RPs sharethe same common search space.

In addition, according to the wireless communication method, the basestation, the transmission/reception point, the user equipment and thewireless communication system of some aspects of the present disclosure,different TP/RPs may have their own TDD UL/DL configuration to adapt totheir own uplink/downlink traffic by transmitting the TDD UL/DLconfiguration in a UE-specific search space. Moreover, the falsedetection and the interference with other TP/RPs may be reduced even fora UE at the edge of a certain TP/RP or in the overlapped area ofmultiple TP/RPs.

The foregoing is a summary and thus contains, by necessity,simplifications, generalization, and omissions of details. Otheraspects, features, and advantages of the devices and/or processes and/orother subject matters described herein will become apparent in theteachings set forth herein. The summary is provided to introduce aselection of concepts in a simplified form that are further describedbelow in the Detailed Description. This summary is not intended toidentify key features or essential features of the claimed subjectmatter, nor is it intended to be used as an aid in determining the scopeof the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the present disclosure willbecome more distinct and easier to be understood in a detaileddescription of embodiments of the present disclosure below incombination with attached drawings, in which:

FIG. 1 is a diagram schematically showing CoMP scenario 4 in LTE;

FIG. 2 is a flowchart showing a wireless communication method by atransmission/reception point according to a first embodiment of thepresent disclosure;

FIG. 3 is a flowchart showing a wireless communication method by a userequipment according to the first embodiment of the present disclosure;

FIG. 4 is a flowchart showing a wireless communication method by atransmission/reception point according to a second embodiment of thepresent disclosure;

FIG. 5 is a flowchart showing a wireless communication method by a userequipment according to the second embodiment of the present disclosure;

FIG. 6 is a flowchart showing a wireless communication method by atransmission/reception point according to a third embodiment of thepresent disclosure;

FIG. 7 is a flowchart showing a wireless communication method by a userequipment according to the third embodiment of the present disclosure;

FIG. 8 is a schematic diagram showing the association between TP/RPnumber and subframe number in a TDD based wireless communication system;

FIG. 9 is a block diagram showing a schematic structure of atransmission/reception point according to the third embodiment of thepresent disclosure;

FIG. 10 is a block diagram showing a schematic structure of a userequipment according to the third embodiment of the present disclosure;

FIG. 11 is a flowchart showing a wireless communication method by atransmission/reception point according to a fourth embodiment of thepresent disclosure;

FIG. 12 is a flowchart showing a wireless communication method by a userequipment according to the fourth embodiment of the present disclosure;and

FIG. 13 is a schematic diagram showing the association between UE groupnumber and subframe number in a TDD based wireless communication system.

DESCRIPTION OF THE EMBODIMENTS

In the following detailed description, reference is made to theaccompanying drawings, which form a part thereof. In the drawings,similar symbols typically identify similar components, unless contextdictates otherwise. It will be readily understood that the aspects ofthe present disclosure can be arranged, substituted, combined, anddesigned in a wide variety of different configurations, all of which areexplicitly contemplated and make part of this disclosure.

First Embodiment

FIG. 2 is a diagram showing a wireless communication method by a basestation according to an implementation of the first embodiment. FIG. 3is a diagram showing a wireless communication method by a user equipment(UE) according to another implementation of the first embodiment.

In the first embodiment, at the (macro) base station side, a wirelesscommunication method of transmitting uplink/downlink (UL/DL)configuration by a base station in a common search space of a wirelesscommunication system is provided. As shown in FIG. 2, the methodcomprises a step 201 of: transmitting the UL/DL configuration to UEs incoverage in a common search space, wherein the UL/DL configuration forthe UE attached to a specific TP/RP is identified by bits in DownlinkControl Information (DCI).

It is to be noted that although FIG. 2 illustrates the wirelesscommunication method by the (macro) base station, since the macro basestation and different TP/RPs share the CSS to transmit (broadcast) theUL/DL configuration, the wireless communication method by a TP/RP issimilarly carried out. That is, a TP/RP transmits the UL/DLconfiguration to UEs in coverage in a common search space, wherein theUL/DL configuration for the UE attached to the TP/RP is identified bybits in DCI.

At the UE side, a wireless communication method of receiving UL/DLconfiguration by a UE in a common search space of a wirelesscommunication system is provided. As shown in FIG. 3, the methodcomprises a step 301 of: receiving the UL/DL configuration in a commonsearch space, wherein the UL/DL configuration for the UE is identifiedby bits in DCI.

Accordingly, a TP/RP of transmitting UL/DL configuration in a wirelesscommunication system is provided, comprising: a transmitter whichtransmits the UL/DL configuration to UEs in the coverage in a commonsearch space, wherein the UL/DL configuration for the UE attached to theTP/RP is identified by bits in DCI.

Also, a (macro) base station of transmitting UL/DL configuration in awireless communication system is provided, comprising: a transmitterwhich transmits the UL/DL configuration to UEs in the coverage in acommon search space, wherein the UL/DL configuration for the UE attachedto a specific TP/RP is identified by bits in DCI.

Also, a UE of receiving UL/DL configuration in a common search space ofa wireless communication system is provided, comprising: a receiverwhich receives the UL/DL configuration in a common search space, whereinthe UL/DL configuration for the UE is identified by bits in DCI.

Also, a wireless communication system is provided, comprising: a basestation, which transmits the UL/DL configuration to UEs in coverage in acommon search space; a TP/RP, which transmits the UL/DL configuration toUEs in coverage in the common search space; and a UE attached to theTP/RP, which receives the UL/DL configuration in the common searchspace, wherein the UL/DL configuration is identified by bits in DCI.

In particular, in the first embodiment, the wireless communicationmethod is applied in a wireless communication system including multipleTP/RPs. The (macro) base station and the multiple TP/RPs share the sameCSS to transmit the UL/DL configuration for all the TP/RPs.

Therefore, to identify the UL/DL configuration for each TP/RP so thatdifferent TP/RPs may have their own UL/DL configuration, an identifierformed of bits in Downlink Control Information (DCI) may be used.

For example, some additional bits are added directly to the DCI foridentifying the UL/DL configuration. Alternatively, some fields in DCImay be reused for such identification. The number of added or reusedbits is associated with the number of TP/RPs. In particular, the addedor reused bits are sufficient to identify each UL/DL configurationpossibility for all of the TP/RPs.

For example, currently there are 7 TDD UL/DL configuration possibilitiesin LTE, which are shown in the following Table 1.

TABLE 1 Uplink-Downlink Configuration in LTE Uplink-DownlinkDownlink-to-Uplink Subframe Number Configuration Switch-PointPeriodicity 0 1 2 3 4 5 6 7 8 9 0 5 ms D S U U U D S U U U 1 5 ms D S UU D D S U U D 2 5 ms D S U D D D S U D D 3 10 ms  D S U U U D D D D D 410 ms  D S U U D D D D D D 5 10 ms  D S U D D D D D D D 6 5 ms D S U U UD S U U D Wherein, “D” refers to a downlink subframe, “U” refers to anuplink subframe, and “S” refers to a special subframe.

Assuming there are three TP/RPs, the identifier needs to identify 7̂3=343UL/DL configuration possibilities. Therefore, at least 9 bits areneeded. With the increase of the TP/RPs, the number of bits increases.For example, assuming there are ten TP/RPs, the identifier needs toidentify 7̂10=282475249 UL/DL configuration possibilities, which means atleast 29 bits.

According to the first embodiment of the present disclosure, each TP/RPmay have its own UL/DL configuration indicated by the identifier in DCI,even when the different TP/RPs share the same common search space.

However, in the first embodiment, it needs some modification to DCI,which means a relatively large impact on the specification. Further, asdescribed above, the identifier may need a large number of bits, if thenumber of TP/RPs is large. Therefore, it needs a great effort on the DCIdesign in the first embodiment.

In addition, there is no splitting gain in the first embodiment. Ifthere is error in some bits, it would result in a wrong identificationfor all the TP/RPs, and thus the system performance will be affectedlargely.

To further decrease the standardization efforts and increase thesplitting gain, a third embodiment of the present disclosure isprovided, which will be described later.

Second Embodiment

FIG. 4 is a diagram showing a wireless communication method by a basestation according to an implementation of the second embodiment. FIG. 5is a diagram showing a wireless communication method by a user equipment(UE) according to another implementation of the second embodiment.

In the second embodiment, at the (macro) base station or the TP/RP side,as shown in FIG. 4, the method comprises a step 401 of: transmitting theUL/DL configuration to UEs in the coverage in a UE group common searchspace (UE-group CSS). Accordingly, at the UE side, as shown in FIG. 5,the method comprises a step 501 of: receiving the UL/DL configuration ina UE group common search space.

In particular, in this embodiment, UEs in the wireless communicationsystem are grouped, for example, based on the different TP/RPs to whichthey are attached. That is, UEs in a certain group may be attached tothe same TP/RP, or attached to different TP/RPs. It is to be noted that,when UEs in a certain group are attached to the same TP/RP, the UE-groupCSS potentially means the TP/RP-specific CSS.

Further, UEs in the same group share the same (e)PDCCH. Therefore,Compared to the CSS which is common to all UEs in the wirelesscommunication system in the first embodiment, the UE-group CSS means asearch space common to a certain UE group out of all UEs, so that UEs ina certain UE group may have the same TP/RP configuration. The UE-groupCSS may be defined in the common search space or the UE-specific searchspace.

According to the second embodiment of the present disclosure, assumingUEs in a group are attached to the same TP/RP, then a certain TP/RPtransmits its own UL/DL configuration in a UE-group CSS specific to thisTP/RP. Accordingly, UEs attached to this TP/RP may receive their UL/DLconfiguration in the same UE-group CSS. Thereby, each TP/RP may have itsown UL/DL configuration to adapt to its own uplink/downlink traffic.

However, in the second embodiment, different UL/DL configuration maystill be transmitted in a UE-group CSS of the same subframe. Therefore,UEs, especially those in the overlapped area of the coverage ofdifferent TP/RPs, may receive different UL/DL configuration in the samesubframe, which may result in some false detections.

To further reduce the false detections and improve the splitting gain, afourth embodiment of the present disclosure is provided, which will bedescribed later.

Third Embodiment

FIG. 6 is a diagram showing a wireless communication method by a basestation according to an implementation of the third embodiment. FIG. 7is a diagram showing a wireless communication method by a UE accordingto another implementation of the third embodiment. Similar to thescenario in the first embodiment, the wireless communication method isalso applied in a wireless communication system including multipleTP/RPs.

At the (macro) base station side, in the wireless communication methodaccording to the third embodiment, as shown in FIG. 6, the methodcomprises a step 601 of transmitting the UL/DL configuration to a UEattached to a specific TP/RP, in a common search space (CSS) of aspecific time/frequency resource associated with the specific TP/RP.

In addition, although it is not shown in FIG. 6, at the TP/RP side,similarly, the method comprises a step of transmitting the UL/DLconfiguration to a user equipment (UE) attached to the TP/RP itself, ina common search space of a specific time/frequency resource associatedwith the TP/RP.

In particular, the (macro) base station and the TP/RPs in the wirelesscommunication system transmit (e.g. broadcast) UL/DL configuration, inthe CSS. More particularly, they transmit the UL/DL configuration forUEs attached to a first TP/RP in a CSS of a first time/frequencyresource, transmit the UL/DL configuration for UEs attached to a secondTP/RP in a CSS of a second time/frequency resource, and so on. In otherwords, for each TP/RP, a specific time/frequency resource associatedwith the TP/RP is assigned for its own UL/DL configuration transmission.The association between the number index of the TP/RP and an index ofthe specific time/frequency resource may be hard coded in advance, forexample. Alternatively, the association may be configured by a highlayer signaling, such as a Radio Resource Control (RRC) signaling or abroadcast signaling (e.g., System Information Block (SIB)).

The number index of the TP/RP (also referred to as the TP/RP numberhereinafter) may be configured by a high layer signaling. For example,the TP/RP number may be configured by a UE-specific Radio ResourceControl (RRC) signaling. Further, the TP/RP number may be only useful toreceive the UL/DL configuration by the UE, and may not necessarily beused to identify the TP/RP in the CoMP operations, so that there is noimpact on the current CoMP.

At the UE side, in the wireless communication method according to thethird embodiment, as shown in FIG. 7, the method comprises a step 701 ofreceiving the UL/DL configuration for the UE, in a common search spaceof a specific time/frequency resource associated with a specific TP/RP;wherein the UE is attached to the specific TP/RP, and the associationbetween a number index of the specific TP/RP and an index of thespecific time/frequency resource is predefined.

In particular, the UE may receive the UL/DL configuration for UEs in thespecific TP/RP from the specific TP/RP and/or from the (macro) basestation in a common search space of the specific time/frequencyresource, since the specific TP/RP and the (macro) base stationbroadcast the same UL/DL configuration in the same CSS.

The index of the specific time/frequency resource may comprise at leastone of a subframe number, a Physical Resource Block (PRB) index, aControl Channel Element (CCE) index, a Enhanced Physical DownlinkControl Channel (EPDCCH) set index and a UE Cell Radio Network TemporaryIdentifier (C-RNTI).

In an example, the association may be an association between the TP/RPnumber and the subframe number indicating the specific subframe which isassigned for the UL/DL configuration transmission, for example in a TDDbased wireless communication system.

In particular, the association may be based on mod(TP/RP number, X),wherein, TP/RP number is the number index of the TP/RP, and X is thenumber of subframes available for UL/DL configuration transmission, forexample equal to 4. The value of X may be configured by the TP/RPaccording to the traffic type etc, as known to those skilled in the art.Such association may be hard coded in standard, or may be indicated by ahigh layer signaling, as described above.

It is to be noted that, the above association of mod(TP/RP number, X) isonly an example, and those skilled in the art may design the associationbased on other expressions, on the basis of the above teaching, whichwill also be fallen within the scope of the present disclosure.

In another example, the association may be an association between theTP/RP number and the PRB or CCE index indicating the specific PRB or CCEwhich is assigned for the UL/DL configuration transmission.Alternatively, the association may be an association between the TP/RPnumber and the (e)PDCCH set index indicating the specific (e)PDCCH setwhich is assigned for the UL/DL configuration transmission.

In a further example, the association may be an association between theTP/RP number and the UE ID (C-RNTI). For example, when there are a smallnumber of UEs in a TDD based wireless communication system, the UEattached to a specific TP/RP may determine the specific subframe basedon the mod (C-RNTI, X), wherein, C-RNTI is the identifier of the UE, andX is the number of subframes available for UL/DL configurationtransmission.

FIG. 8 is a schematic diagram showing the association between the TP/RPnumber and the subframe number in a TDD based wireless communicationsystem. In FIG. 8, the upper part is a row indicating the UL/DLconfiguration 1 as shown in Table 1. The lower part is a schematic CoMPscenario 800 comprising three TP/RPs 801-803, wherein, a UE 804 isattached to the TP/RP 801, a UE 805 is attached to the TP/RP 802, and aUE 806 is attached to the TP/RP 806. It is to be noted that the macrobase station is not shown in this figure for clearly illustrating theembedment of the present disclosure. According to the third embodiment,the UE 804 only expect to receive its own TDD UL/DL configuration insubframe #0, the UE 805 only expect to receive its own TDD UL/DLconfiguration in subframe #1, and the UE 806 only expect to receive itsown TDD UL/DL configuration in subframe #5.

Of course, the above kinds of association are only examples, and thepresent disclosure is not limited thereto. In addition, the above kindsof association may be combined with each other when appropriate,especially when there is a large number of TP/RPs.

For example, the following Table 2 is an example of the associationbetween the TP/RP number and the subframe number in a TDD based wirelesscommunication system including 12 TP/RPs. Assuming there are 4 subframesavailable for UL/DL configuration transmission in total. Since thenumber of TP/RPs is larger than the available subframes, the TP/RPsneeds to be grouped into groups as described in the second and thefourth embodiment, so that more than one (in this example, 3) TP/RPscorrespond to the same subframe. Therefore, for each TP/RP in a certaingroup, another index may be necessary to further indicate the specifictime/frequency resource associated with the TP/RP.

TABLE 2 subframe dependent configuration of (group) CSS Subframe #0Subframe #1 Subframe #5 Subframe #6 TP/RP index 1, 2, 3 4, 5, 6 7, 8, 910, 11, 12 expecting to receive (group) CSS

In this case, in addition to the subframe number, another indexindicating the frequency position in frequency domain, for example theCCE index or the PRB index, may be used. The CCE index or the PRB indexmay be an index indicating the starting position of the CSS for theUL/DL configuration transmission. Therefore, not only the specificsubframe assigned for TP/RP may be determined, but also specific CCE(s)or specific PRB(s) in the specific subframe may be determined.

Alternatively, in addition to the subframe number, similar to that inthe first embodiment, an identifier for identifying the UL/DLconfiguration for the UE attached to the specific TP/RP may be used inthis case. The identifier may be formed of bits in Downlink ControlInformation (DCI), as described in the first embodiment. However,compared to the identifier in the first embodiment, the number of bitsof the identifier is considerably reduced. For example, in the case ofTable 2, since there are totally 12 TP/RPs, the identifier needs toidentify 7̂12=13841287201 kinds of UL/DL configuration possibilitiesaccording to the first embodiment. However, according to the thirdembodiment, since TP/RPs in different groups transmit UL/DLconfiguration in different subframes, the identifier only needs toidentify the UL/DL configuration for TP/RPs in the same group, i.e., 3TP/RPs in this case. In other words, the identifier needs to identify7̂3=343 kinds of UL/DL configuration possibilities. Of course, the numberof bits of the identifier can be largely reduced.

In other implementations of the third embodiment, a UE of receivingUL/DL configuration, and a TP/RP of transmitting UL/DL configuration areprovided. The UE and the TP/RP are also applied in the wirelesscommunication system includes multiple TP/RPs.

FIG. 9 is a block diagram showing the schematic structure of a basestation 900 according to the third embodiment of the present disclosure.As shown in FIG. 9, the base station 900 comprises a transmitter 901which transmits the UL/DL configuration to a UE, in a common searchspace of a specific time/frequency resource associated with a specificTP/RP, wherein, the UE is attached to the specific TP/RP, and theassociation between number index of the specific TP/RP and an index ofthe specific time/frequency resource is predefined.

The base station 900 according to the third embodiment may optionallyinclude a CPU (Central Processing Unit) 910 for executing relatedprograms to process various data and control operations of respectiveunits in the TP/RP 900, a ROM (Read Only Memory) 913 for storing variousprograms required for performing various process and control by the CPU910, a RAM (Random Access Memory) 915 for storing intermediate datatemporarily produced in the procedure of process and control by the CPU910, and/or a storage unit 917 for storing various programs, data and soon. The above transmitter 901, CPU 910, ROM 913, RAM 915 and/or storageunit 917 etc. may be interconnected via data and/or command bus 920 andtransfer signals between one another.

Respective units as described above do not limit the scope of thepresent disclosure. According to one implementation of the disclosure,the functions of the above transmitter 901 may be implemented byhardware, and the above CPU 910, ROM 913, RAM 915 and/or storage unit917 may not be necessary. Alternatively, the functions of the abovetransmitter 901 may also be implemented by functional software incombination with the above CPU 910, ROM 913, RAM 915 and/or storage unit917 etc.

Also, although it is not shown, the TP/RP according to the thirdembodiment has a similar structure to the (macro) base station 900 inFIG. 9. That is, the TP/RP comprises a transmitter which transmits theUL/DL configuration to a user equipment (UE), in a common search spaceof a specific time/frequency resource associated with the TP/RP,wherein, the UE is attached to the TP/RP, and the association betweennumber index of the TP/RP and an index of the specific time/frequencyresource is predefined.

FIG. 10 is a diagram showing a schematic structure of a UE 1000according to the third embodiment of the present disclosure. As shown inFIG. 10, the UE 1000 comprises a receiver 1001 which receives the UL/DLconfiguration for the UE in a common search space of a specifictime/frequency resource associated with a specific TP/RP, wherein, theUE is attached to the specific TP/RP, and the association between numberindex of the specific TP/RP, and an index of the specific time/frequencyresource is predefined.

The UE 1000 according to the third embodiment may optionally include aCPU (Central Processing Unit) 1010 for executing related programs toprocess various data and control operations of respective units in theUE 1000, a ROM (Read Only Memory) 1013 for storing various programsrequired for performing various process and control by the CPU 1010, aRAM (Random Access Memory) 1015 for storing intermediate datatemporarily produced in the procedure of process and control by the CPU1010, and/or a storage unit 1017 for storing various programs, data andso on. The above receiver 1001, CPU 1010, ROM 1013, RAM 1015 and/orstorage unit 1017 etc. may be interconnected via data and/or command bus1020 and transfer signals between one another.

Respective units as described above do not limit the scope of thepresent disclosure. According to one implementation of the disclosure,the functions of the above receiver 1001 may be implemented by hardware,and the above CPU 1010, ROM 1013, RAM 1015 and/or storage unit 1017 maynot be necessary. Alternatively, the functions of the above receiver1001 may also be implemented by functional software in combination withthe above CPU 1010, ROM 1013, RAM 1015 and/or storage unit 1017 etc.

Accordingly, in another implementation, a wireless communication systemis provided, comprising: a first transmission/reception point (TP/RP),which transmits a first uplink/downlink (UL/DL) configuration to userequipments (UEs) in its coverage in a common search space of a firsttime/frequency resource associated with the first TP/RP; a second TP/RP,which transmits a second UL/DL configuration to UEs in its coverage in acommon search space of a second time/frequency resource associated withthe second TP/RP; a base station which transmits the firstuplink/downlink UL/DL configuration to UEs in its coverage in the commonsearch space of the first time/frequency resource, and transmits thesecond UL/DL configuration to UEs in its coverage in the common searchspace of the second time/frequency resource; a first UE attached to thefirst TP/RP, which receives the first UL/DL configuration in the commonsearch space of the first time/frequency resource; and a second UEattached to the second TP/RP, which receives the second UL/DLconfiguration in the common search space of the second time/frequencyresource; wherein, the association between a number index of TP/RP andan index of time/frequency resource is predefined at the base station,the first TP/RP, the second TP/RP, the first UE and the second UE.

According to the above implementations of the third embodiment, theUL/DL configuration transmission is dependent on the time/frequencyresource unit. For example, in a TDD based communication system, theUL/DL configuration transmission is subframe-dependent. Therefore, evenwhen there are multiple TP/RPs sharing the same CSS in the CoMPscenario, each TP/RP can have its own UL/DL configuration so as to adaptto its own UL/DL traffic.

Further, according to the third embodiment of the present disclosure,there is potentially no need to add bits to the existing CSS based DCIor reuse some bits in the DCI for identifying the UL/DL configuration,especially when there is a relatively small number of TP/RPs in thesystem. Therefore, there is less standardization effort.

In addition, since UL/DI configuration for different TP/RPs istransmitted in different time/frequency resources, there is a splittinggain in the corresponding time/frequency domain.

In the above implementations of the third embodiment, the UL/DLconfiguration is transmitted in CSS. Alternatively, in otherimplementations as described hereinafter, the UL/DL configuration mayalso be transmitted in UE-specific search space (USS).

In this implementation, at the UE side, the method comprises a step of:receiving the UL/DL configuration for the UE from a specific TP/RP, in aUE specific search space of a specific time/frequency resourceassociated with the specific TP/RP, wherein, the UE is attached to thespecific TP/RP, and the association between a number index of thespecific TP/RP and an index of the specific time/frequency resource ispredefined.

At the TP/RP side, the method comprises a step of: transmitting UL/DLconfiguration to a UE attached to the TP/RP, in a UE specific searchspace of a specific time/frequency resource associated with the TP/RP;wherein, the association between a number index of the TP/RP and anindex of the specific time/frequency resource is predefined.

In particular, in this implementation, the (macro) base station does nottransmit UL/DL configuration, while each TP/RP transmits its own TP/RPin a USS of a time/frequency resource associated with the TP/RP itself.The association is similar to those described in the aboveimplementation, and will not be described here in detail.

Accordingly, in this implementation, a UE is provided, comprising: areceiver which receives the UL/DL configuration for the UE from aspecific TP/RP, in a UE specific search space of a specifictime/frequency resource associated with the specific TP/RP, wherein, theUE is attached to the specific TP/RP, and the association between anumber index of the specific TP/RP and an index of the specifictime/frequency resource is predefined.

Also, a TP/RP is provided, comprising: a transmitter which transmitsUL/DL configuration to a UE attached to the TP/RP, in a UE specificsearch space of a specific time/frequency resource associated with theTP/RP; wherein, the association between a number index of the TP/RP andan index of the specific time/frequency resource is predefined.

Also, a wireless communication system is provided, comprising: a basestation; a first TP/RP which transmits a first UL/DL configuration toUEs in its coverage, in a UE specific common search space of a firsttime/frequency resource; a second TP/RP which transmits a second UL/DLconfiguration to UEs in its coverage, in a UE specific common searchspace of a second time/frequency resource; a first UE attached to thefirst TP/RP, which receives the first UL/DL configuration from the firstTP/RP, in the UE specific common search space of the firsttime/frequency resource; and a second UE attached to the second TP/RP,which receives the second UL/DL configuration from the second TP/RP, inthe UE specific common search space of the second time/frequencyresource; wherein, the association between a number index of TP/RP andan index of time/frequency resource is predefined at the first TP/RP,the second TP/RP, the first UE and the second UE.

The structures of the TP/RP and the UE in this implementation aresimilar to those in the above implementation described with reference toFIGS. 9 and 10, and will not be described here in detail.

According to this implementation, even when there are multiple TP/RPs inthe CoMP scenario, each TP/RP can transmit its own UL/DL configurationto the attached UEs in a USS, so as to adapt to its own UL/DL traffic.

Further, according to this implementation, even for a UE at the edge ofa certain TP/RP's coverage or in an overlapped area of multiple TP/RPs'coverage, since different TP/RPs transmit their UL/DL configuration indifferent time/frequency resources, it can correctly receive the UL/DLconfiguration from the specific TP/RP to which it is attached, therebyreducing the false detection and the interference caused by otherTP/RPs.

Fourth Embodiment

FIG. 11 is a diagram showing a wireless communication method by a basestation according to an implementation of the fourth embodiment. FIG. 12is a diagram showing a wireless communication method by a UE accordingto another implementation of the fourth embodiment. Similar to thescenario in the first embodiment, the wireless communication method isalso applied in a wireless communication system including multipleTP/RPs.

At the (macro) base station side, as shown in FIG. 11, the methodcomprises a step 1101 of: transmitting the UL/DL configuration to a UE,in a UE group common search space of a CSS of a specific time/frequencyresource associated with a specific UE group, wherein, the UE is groupedinto the specific UE group, and the association between number index ofthe specific UE group and an index of the specific time/frequencyresource is predefined.

Also, although it is not shown in FIG. 11, similarly, at the TP/RP side,the method comprises a step of: transmitting the UL/DL configuration toa UE, in a UE group common search space of a common search space of aspecific time/frequency resource associated with a specific UE group,wherein, the UE is grouped into the specific UE group, and theassociation between number index of the specific UE group and an indexof the specific time/frequency resource is predefined.

At the UE side, as shown in FIG. 12, the method comprises a step 1201of: receiving the UL/DL configuration for the UE in a UE group commonsearch space of the CSS of a specific time/frequency resource associatedwith a specific UE group, wherein, the UE is grouped into the specificUE group, and the association between number index of the specific UEgroup, and an index of the specific time/frequency resource ispredefined.

The meaning of UE group CSS and related detailed process have beendescribed in the second embodiment, and will not be described here toavoid redundancy. Different from those in the second embodiment, in thefourth embodiment, the TP/RP transmits the UL/DL configuration in thespecific time/frequency resource as described above in the thirdembodiment. The specific time/frequency resource is associated with aspecific UE group. Thereby, a UE in the specific group may only receiveits UL/DL configuration in the specific time/frequency resource.

Similar to those in the third embodiment, the index may comprise atleast one of a subframe number, a Physical Resource Block (PRB) index, aControl Channel Element (CCE) index, a Enhanced Physical DownlinkControl Channel (EPDCCH) set index and a UE Cell Radio Network TemporaryIdentifier (C-RNTI). However, different from the association ofmod(TP/RP number X) in the third embodiment, in this embodiment, theassociation may be based on mod(UE group number, X), wherein, UE groupnumber is the number index of the UE group, and X is the number ofsubframes available for UL/DL configuration transmission, for exampleequal to 4. Similarly, the UE group number may be configured by a highlayer signaling.

In this implementation, the UE group CSS is defined in the CSS shared bythe (macro) base station and the TP/RPs. Since UEs in different UEgroups receive the UL/DL configuration in different time/frequencyresources, different UE groups, which may potentially means differentTP/RPs, may still have their own UL/DL configuration, even when theyshare the same UE group CSS in the CSS.

Alternatively, in another implementation, the UE group CSS may bedefined in the USS. In this implementation, as described in the secondembodiment, only the TP/RPs transmit their own UL/DL configurations.

In detail, at the TP/RP side, the method comprises a step of:transmitting the UL/DL configuration to a UE attached to the TP/RP, in aUE group common search space of a UE specific search space of a specifictime/frequency resource associated with a specific UE group; wherein,the UE is grouped into the specific UE group, and the associationbetween a number index of the specific UE group and an index of thespecific time/frequency resource is predefined.

At the UE side, the method comprises a step of: receiving the UL/DLconfiguration for the UE from a TP/RP to which it is attached, in a UEgroup common search space of a UE specific search space of a specifictime/frequency resource associated with a specific UE group, wherein,the UE is grouped into the specific UE group, and the associationbetween a number index of the specific UE group and an index of thespecific time/frequency resource is predefined.

In this implementation, different TP/RPs may transmit their own TP/RPconfiguration in the USS. Moreover, since different TP/RPs transmittheir own TP/RP configuration in different time/frequency resource, evenfor a UE at the edge of a certain TP/RP's coverage or in an overlappedarea of multiple TP/RPs' coverage, it can correctly receive the UL/DLconfiguration from the specific TP/RP to which it is attached, therebyreducing the false detection and the interference caused by otherTP/RPs.

For example, FIG. 13 is a schematic diagram showing the associationbetween the UE group number and the subframe number in a TDD basedwireless communication system. In FIG. 13, the upper part is a rowindicating a UL/DL configuration. The lower part is a schematic wirelesscommunication system 1300 comprising two TP/RPs 1301 and 1302. Also,assuming that UEs attached to the same TP/RP forms a UE group, then UEsof the UE group in the TP/RP 1301 (e.g., UE 1303) may only expect toreceive the UL/DL configuration in subframe #0 and subframe #1, and UEsof the UE group in the TP/RP 1302 (e.g., UE 1304) may only expect toreceive the UL/DL configuration in subframe #5 and subframe #6. Thereby,different UE group, which potentially means different TP/RPs, may havetheir own UL/DL configuration, no matter the UE-group CSS is defined inCSS or the USS.

Further, assuming that the UL/DL configuration is transmitted in a UEgroup CSS in the USS. Then, even for a UE at the edge of a certainTP/RP's coverage or in an overlapped area of multiple TP/RPs' coverage,for example UE 1303, it may only expect to receive the UL/DLconfiguration in subframe #0 and subframe #1 since it belongs to the UEgroup attached to the TP/RP 1301. Thereby, the false detection by the UEand the interference with other TP/RPs are reduced.

The base station or the TP/RP according to an implementation of thefourth embodiment which comprises a transmitter may have a similarconfiguration as the base station 900 or the TP/RP according to thethird embodiment except the following. The transmitter according to thisimplementation of the fourth embodiment may transmit the UL/DLconfiguration to a UE, in a UE group common search space of a CSS of aspecific time/frequency resource associated with a specific UE group;wherein, the UE is grouped into the specific UE group, and theassociation between a number index of the specific UE group and an indexof the specific time/frequency resource is predefined.

Accordingly, the UE according to an implementation of the fourthembodiment which comprises a receiver may have a similar configurationas the UE 1000 according to the third embodiment except the following.The receiver according to this implementation of the fourth embodimentmay receive the UL/DL configuration for the UE, in a UE group commonsearch space of a CSS of a specific time/frequency resource associatedwith a specific UE group, wherein, the UE is grouped into the specificUE group, and the association between a number index of the specific UEgroup and an index of the specific time/frequency resource ispredefined.

Accordingly, the wireless communication system according to animplementation of the fourth embodiment comprises: a first TP/RP, whichtransmits a first UL/DL configuration to UEs in its coverage, in a UEgroup common search space of a common search space of a firsttime/frequency resource associated with a first UE group; a secondTP/RP, which transmits a second UL/DL configuration to UEs in itscoverage, in a UE group common search space of a common search space ofa second time/frequency resource associated with a second UE group; abase station which transmits the first UL/DL configuration to UEs in itscoverage in the UE group common search space of the common search spaceof the first time/frequency resource, and transmits a second UL/DLconfiguration to UEs in its coverage in the UE common group search spaceof the common search space of the second time/frequency resource; afirst UE in the first UE group, which receives the first UL/DLconfiguration, in the UE group common search space of the common searchspace of the first time/frequency resource; and a second UE in thesecond UE group, which receives the second UL/DL configuration, in theUE group common search space of the common search space of the secondtime/frequency resource; wherein, the association between a number indexof UE group and an index of time/frequency resource is predefined at thebase station, the first TP/RP, the second TP/RP, the first UE and thesecond UE.

Also, according to another implementation of the present disclosure, theTP/RP which comprises a transmitter may have a similar configuration asthe TP/RP according to the third embodiment except the following. Thetransmitter according to this implementation of the fourth embodimentmay transmit the UL/DL configuration to a UE attached to the TP/RP, in aUE group common search space of a UE specific search space of a specifictime/frequency resource associated with a specific UE group; wherein,the UE is grouped into the specific UE group, and the associationbetween a number index of the specific UE group and an index of thespecific time/frequency resource is predefined.

Accordingly, the UE according to an implementation of the fourthembodiment which comprises a receiver may have a similar configurationas the UE 1000 according to the third embodiment except the following.The receiver according to this implementation of the fourth embodimentmay receive the UL/DL configuration for the UE from a TP/RP to which itis attached, in a UE group common search space of a UE specific searchspace of a specific time/frequency resource associated with a specificUE group, wherein, the UE is grouped into the specific UE group, and theassociation between a number index of the specific UE group and an indexof the specific time/frequency resource is predefined.

Accordingly, the wireless communication system according to thisimplementation of the fourth embodiment comprises: a base station; afirst TP/RP, which transmits a first UL/DL configuration to UEs in itscoverage, in a UE group common search space of a UE specific searchspace of a first time/frequency resource associated with a first UEgroup; a second TP/RP which transmits a second UL/DL configuration toUEs in its coverage, in a UE group common search space of a UE specificsearch space of a second time/frequency resource associated with asecond UE group; a first UE in the first UE group, which receives thefirst UL/DL configuration from the first TP/RP, in the UE group commonsearch space of the UE specific search space of the first time/frequencyresource; and a second UE in the second UE group, which receives thesecond UL/DL configuration from the second TP/RP, in the UE group commonsearch space of the UE specific search space of the secondtime/frequency resource; wherein, the association between a number indexof UE group and an index of time/frequency resource is predefined at thefirst TP/RP, the second TP/RP, the first UE and the second UE.

The other parts and process of the fourth embodiment are similar tothose described in the second or third embodiment, and will not bedescribed here to avoid redundancy.

The above embodiments of the present disclosure are only exemplarydescription, and their specific structures and operations do not limitthe scope of the disclosure. Those skilled in the art can recombinedifferent parts and operations of the above respective embodiments toproduce new implementations which equally accord with the concept of thepresent disclosure.

The embodiments of the present disclosure may be implemented byhardware, software and firmware or in a combination thereof, and the wayof implementation does not limit the scope of the present disclosure.

The connection relationships between the respective functional elements(units) in the embodiments of the disclosure do not limit the scope ofthe present disclosure, in which one or multiple functional element(s)or unit(s) may contain or be connected to any other functional elements.

Although several embodiments of the present disclosure has been shownand described in combination with attached drawings above, those skilledin the art should understand that variations and modifications whichstill fall into the scope of claims and their equivalents of the presentdisclosure can be made to these embodiments without departing from theprinciple and spirit of the disclosure.

1-9. (canceled)
 10. A wireless communication method of receivinguplink/downlink (UL/DL) configuration by a user equipment (UE), in awireless communication system including multiple transmission/receptionpoints (TP/RPs), comprising a step of: receiving the UL/DL configurationfor the UE in a UE group common search space of a common search space ofa specific time/frequency resource associated with a specific UE group,wherein, the UE is grouped into the specific UE group, and theassociation between a number index of the specific UE group and an indexof the specific time/frequency resource is predefined.
 11. The wirelesscommunication method according to claim 10, wherein the association ishard coded, or indicated by a high-layer signaling.
 12. The wirelesscommunication method according to claim 10, wherein the index comprisesat least one of a subframe number, a Physical Resource Block (PRB)index, a Control Channel Element (CCE) index, a Enhanced PhysicalDownlink Control Channel (EPDCCH) set index and a UE Cell Radio NetworkTemporary Identifier (C-RNTI).
 13. The wireless communication methodaccording to claim 10, wherein the number index of the specific UE groupis associated with a subframe number indicating a specific subframewhich is assigned for Time Division Duplexing (TDD) UL/DL configurationtransmission; and the association is based on mod(UE group number, X),wherein, UE group number is the number index of the specific UE group,and X is the number of subframes available for the TDD UL/DLconfiguration transmission.
 14. The wireless communication methodaccording to claim 10, wherein the number index of the specific UE groupis associated with a subframe number indicating a specific subframewhich is assigned for Time Division Duplexing (TDD) UL/DL configurationtransmission; and the TDD UL/DL configuration for the UE in the specificUE group is further identified by bits in Downlink Control Information(DCI), when the number of UE groups is larger than the number ofsubframes available for the TDD UL/DL configuration transmission. 15.The wireless communication method according to claim 10, wherein thenumber index of the specific UE group is associated with a subframenumber indicating a specific subframe which is assigned for TimeDivision Duplexing (TDD) UL/DL configuration transmission; and the TDDUL/DL configuration for the UE in the specific UE group is furtheridentified by at least one of a Physical Resource Block (PRB) index, aControl Channel Element (CCE) index, a Enhanced Physical DownlinkControl Channel (EPDCCH) set index and a UE Cell Radio Network TemporaryIdentifier (C-RNTI), when the number of UE groups is larger than thenumber of subframes available for the TDD UL/DL configurationtransmission.
 16. A wireless communication method of transmittinguplink/downlink (UL/DL) configuration by a base station, in a wirelesscommunication system including multiple transmission/reception points(TP/RPs), comprising a step of: transmitting the UL/DL configuration toa user equipment (UE), in a UE group common search space of a commonsearch space of a specific time/frequency resource associated with aspecific UE group; wherein, the UE is grouped into the specific UEgroup, and the association between a number index of the specific UEgroup and an index of the specific time/frequency resource ispredefined.
 17. A wireless communication method of receivinguplink/downlink (UL/DL) configuration by a user equipment (UE), in awireless communication system including multiple transmission/receptionpoints (TP/RPs), comprising a step of: receiving the UL/DL configurationfor the UE from a TP/RP to which it is attached, in a UE group commonsearch space of a UE specific search space of a specific time/frequencyresource associated with a specific UE group, wherein, the UE is groupedinto the specific UE group, and the association between a number indexof the specific UE group and an index of the specific time/frequencyresource is predefined.
 18. A wireless communication method oftransmitting uplink/downlink (UL/DL) configuration by atransmission/reception point (TP/RP), in a wireless communication systemincluding multiple TP/RPs, comprising a step of: transmitting the UL/DLconfiguration to a user equipment (UE) attached to the TP/RP, in a UEgroup common search space of a UE specific search space of a specifictime/frequency resource associated with a specific UE group; wherein,the UE is grouped into the specific UE group, and the associationbetween a number index of the specific UE group and an index of thespecific time/frequency resource is predefined. 19-27. (canceled)
 28. Auser equipment (UE) of receiving uplink/downlink (UL/DL) configuration,in a wireless communication system including multipletransmission/reception points (TP/RPs), comprising: a receiver whichreceives the UL/DL configuration for the UE in a UE group common searchspace of a common search space of a specific time/frequency resourceassociated with a specific UE group, wherein, the UE is grouped into thespecific UE group, and the association between a number index of thespecific UE group and an index of the specific time/frequency resourceis predefined.
 29. The user equipment according to claim 28, wherein theassociation is hard coded, or indicated by a high-layer signaling. 30.The user equipment according to claim 28, wherein the index comprises atleast one of a subframe number, a Physical Resource Block (PRB) index, aControl Channel Element (CCE) index, a Enhanced Physical DownlinkControl Channel (EPDCCH) set index and a UE Cell Radio Network TemporaryIdentifier (C-RNTI).
 31. The user equipment according to claim 28,wherein the number index of the specific UE group is associated with asubframe number indicating a specific subframe which is assigned forTime Division Duplexing (TDD) UL/DL configuration transmission; and theassociation is based on mod(UE group number, X), wherein, UE groupnumber is the number index of the specific UE group, and X is the numberof subframes available for the TDD UL/DL configuration transmission. 32.The user equipment according to claim 28, wherein the number index ofthe specific UE group is associated with a subframe number indicating aspecific subframe which is assigned for Time Division Duplexing (TDD)UL/DL configuration transmission; and the TDD UL/DL configuration forthe UE in the specific UE group is further identified by bits inDownlink Control Information (DCI), when the number of UE groups islarger than the number of subframes available for the TDD UL/DLconfiguration transmission.
 33. The user equipment according to claim28, wherein the number index of the specific UE group is associated witha subframe number indicating a specific subframe which is assigned forTime Division Duplexing (TDD) UL/DL configuration transmission; and theTDD UL/DL configuration for the UE in the specific UE group is furtheridentified by at least one of a Physical Resource Block (PRB) index, aControl Channel Element (CCE) index, a Enhanced Physical DownlinkControl Channel (EPDCCH) set index and a UE Cell Radio Network TemporaryIdentifier (C-RNTI), when the number of UE groups is larger than thenumber of subframes available for the TDD UL/DL configurationtransmission.
 34. A base station of transmitting uplink/downlink (UL/DL)configuration, in a wireless communication system including multipletransmission/reception points (TP/RPs), comprising: a transmitter whichtransmits the UL/DL configuration to a user equipment (UE), in a UEgroup common search space of a common search space of a specifictime/frequency resource associated with a specific UE group; wherein,the UE is grouped into the specific UE group, and the associationbetween a number index of the specific UE group and an index of thespecific time/frequency resource is predefined.
 35. A user equipment(UE) of receiving uplink/downlink (UL/DL) configuration, in a wirelesscommunication system including multiple transmission/reception points(TP/RPs), comprising: a receiver which receives the UL/DL configurationfor the UE from a TP/RP to which it is attached, in a UE group commonsearch space of a UE specific search space of a specific time/frequencyresource associated with a specific UE group, wherein, the UE is groupedinto the specific UE group, and the association between a number indexof the specific UE group and an index of the specific time/frequencyresource is predefined.
 36. A transmission/reception point (TP/RP) oftransmitting uplink/downlink (UL/DL) configuration, in a wirelesscommunication system including multiple TP/RPs, comprising: atransmitter which transmits the UL/DL configuration to a user equipment(UE) attached to the TP/RP, in a UE group common search space of a UEspecific search space of a specific time/frequency resource associatedwith a specific UE group; wherein, the UE is grouped into the specificUE group, and the association between a number index of the specific UEgroup and an index of the specific time/frequency resource ispredefined. 37-38. (canceled)
 39. A wireless communication system,comprising: a first transmission/reception point (TP/RP), whichtransmits a first UL/DL configuration to user equipments (UEs) in itscoverage, in a UE group common search space of a common search space ofa first time/frequency resource associated with a first UE group; asecond TP/RP, which transmits a second UL/DL configuration to UEs in itscoverage, in a UE group common search space of a common search space ofa second time/frequency resource associated with a second UE group; abase station which transmits the first UL/DL configuration to UEs in itscoverage in the UE group common search space of the common search spaceof the first time/frequency resource, and transmits a second UL/DLconfiguration to UEs in its coverage in the UE common group search spaceof the common search space of the second time/frequency resource; afirst UE in the first UE group, which receives the first UL/DLconfiguration, in the UE group common search space of the common searchspace of the first time/frequency resource; and a second UE in thesecond UE group, which receives the second UL/DL configuration, in theUE group common search space of the common search space of the secondtime/frequency resource; wherein, the association between a number indexof UE group and an index of time/frequency resource is predefined at thebase station, the first TP/RP, the second TP/RP, the first UE and thesecond UE.
 40. A wireless communication system, comprising: a basestation; a first transmission/reception point (TP/RP), which transmits afirst UL/DL configuration to user equipments (UEs) in its coverage, in aUE group common search space of a UE specific search space of a firsttime/frequency resource associated with a first UE group; a second TP/RPwhich transmits a second UL/DL configuration to UEs in its coverage, ina UE group common search space of a UE specific search space of a secondtime/frequency resource associated with a second UE group; a first UE inthe first UE group, which receives the first UL/DL configuration fromthe first TP/RP, in the UE group common search space of the UE specificsearch space of the first time/frequency resource; and a second UE inthe second UE group, which receives the second UL/DL configuration fromthe second TP/RP, in the UE group common search space of the UE specificsearch space of the second time/frequency resource; wherein, theassociation between a number index of UE group and an index oftime/frequency resource is predefined at the first TP/RP, the secondTP/RP, the first UE and the second UE